Across Essex’s coastal villages in the summer of 2025, many residents have noticed a spectacular influx of the bright orange-and-black-striped Episyrphus balteatus, known as marmalade hoverflies. These tiny flying insects—often mistaken for wasps—have been gathering in surprisingly large numbers, especially around gardens, hedgerows, and coastal wildlife spots.
🍊 Why Are They Swarming?
Migration from Continent
Each year, millions of marmalade hoverflies migrate from southern Europe, crossing the Channel on warm winds (which is why swarms of them are often spotted on Essex and South East Coastlines). Records suggest they arrive in coastal regions around spring to early summer.
Breeding & Hibernation Routines
They’re active nearly year-round—with larvae overwintering and adults emerging on sunny days—even in winter . This combination of migration and local hibernation leads to sudden swarms in summer.
👌 Are They a Threat?
No—quite the opposite! Marmalade hoverflies are harmless to humans and pets:
They cannot sting or bite
Pose no health risk or property damage
They don’t reproduce indoors or behave invasively
They’re simply peaceful pollinators with high energy—hovering near flowers and bright surfaces.
🐝 How to Tell Them Apart From Wasps
Marmalade hoverflies and wasps can appear similar at first glance due to their black and yellow colouring, but there are key visual differences. Marmalade hoverflies are generally smaller and have a more rounded, fly-like body with large, prominent eyes and short antennae.
Their wings are clear and held out to the sides when at rest, and they have a distinctive orange-and-black banded abdomen.
In contrast, wasps have a more defined waist, longer bodies, and pointed abdomens with smoother, shinier exoskeletons. They also have longer antennae and their wings are typically folded lengthwise when not flying.
🌼 Why They Matter for Gardens & Ecosystems
Superb Pollinators
Hoverflies are the second most important pollinator group after bees. Marmalade hoverflies, specifically, visit over half of all food crops in the UK (e.g., carrots, strawberries), and thrive from tiny yellow wildflowers to garden blooms.
Natural Pest Controllers
Their larvae are voracious aphid predators, consuming up to 300–400 aphids each—making them invaluable for gardeners and farmers.
Vital to Biodiversity
Hoverflies support wildlife food chains, freeloading any garden ecosystem with pollination and biological pest control. Their presence reduces pesticide reliance and boosts plant diversity.
🐝 Mimicry & Identification
Marmalade hoverflies display Batesian mimicry—they appear like wasps to deter predators, yet they’re entirely harmless. Adults measure around 9–12 mm, with orange bodies sporting two distinct black bands (“moustache” stripes).
📆 Seasonal Patterns & Population Trends
January–December: Active nearly all year round, with spring emergence from overwintering adults.
Summer Spike: Coastal Essex sees significant numbers in June–August, driven by migrant arrival.
Yearly Fluctuations: Populations can vary—warmer summers and abundant flowers boost numbers, while cold or dry springs suppress arrivals.
🌳 What You Can Do to Help
Attract them to gardens by planting nectar-rich flowers, especially yellow blooms, cow parsley, fennel, asters, and ivy.
Support breeding with habitats like hoverfly lagoons—shallow water dishes with leaves and logs.
Monitor their presence to help local conservation efforts—watch their arrival and feeding sites.
🌟 Bumblebee Substitute in Pollination Action
With bees facing habitat loss and pesticide threats, hoverflies are poised to fill key pollination roles, especially for small flowers and food crops. Their resilience and migratory pattern help buffer ecosystem services—ensuring crops and wild plants are fertilised year to year.
✅ The Takeaway
That vibrant, buzzing influx of marmalade hoverflies in Essex is good news for gardens and biodiversity. They aren’t pests—they’re allies: pollinating the blooms, eating aphids, and supporting nature’s balance. No action is needed—just admire them, let them feast, and feel good about their natural role.
📬 Want to Know More?
If you have any other questions about Marmalade Hoverflies, reach out for a friendly chat with a member of our team today.
